Stoker for furnaces.



N0.'864,946. PATENTED SEPT; 3, 1907.

- E. BRETNEY.

STOKER'FOR FURNACES.

- APPLICATION FILED r213. 16. 1907.

2 SHEETS-SHHET 1- aww No. 864,946. PATENTED SEPT. 3, 1907.

5. BRETNEY. STOKER FOR FURNACES.

APPLICATION FILED FEB-1B. 1907.

I 2 SHEETS-SHEET 2.

W/ TIVESSESZ //VVA/ ,5 My ,Ezgyeneflrane y,

UNITED STATES PATENT OFFICE.

EUGENE BRETNEY, OF INDIANAPOLIS, INDIANA, ASSIGNOR OF TWO-THIRDS ToEDWARD H.

SCHMIDT AND L; PVROTHCHILD, OF INDIANAPOLIS, INDIANA.

I STOKER FOR FURNACES;

Specification of Letters Patent.

Application filed mangle- 190v. Serial No. 358.090.

To all whom it mag concern:

Be it known that I, EUGENE BRETNEY, a citizen of' the United States,residing at Indianapolis, in the .county of Marion and State of'Indiana,havejnvented certain new and useful Improvements inStokers for Furnaces,of which the following is a specification.

This invention relates, to improvements in grates for furnace fires forsteam heating plants, and similar purposes, and theobject of theinvention is to provide endless traveling grate-bars mounted obliquelyto the horizontal, and sloping downwardly from front to rear of thelire-box, said gtate-bars being mounted on a track on a suitably wheeledtruck topermit of ready withdrawal from under the boilers for cleaningand repairs.

Another and important object of the invention is to provide ascrew-conveyer for carrying the fuel from front to rear of thegratebars, underneath the-latter, and screw .conveying means forelevating the fuel and discharging it upon the lower rear end of thetraveling grate-bars.

I accomplish the objects of the invention by the mechanism illustratedin the accompanying drawings, in which Figure 1 is a detail in verticalsection of a fire-box equipped with my invention, the view being takenon a plane extending from front to rear ofthe fire-box at right anglesto the furnace-front. Fig.2 is a detail in vertical section on the line2-2 of Fig.' 1, and'Fig. 3 is a horizontal section of one of thevertical screw-conveyers.

Like characters of reference indicate like parts throughout the severalviews of the drawings. I

5 represents a' boiler for generating steam, .of any usual and suitableconstruction, here shown as a tubu- 9 is a truck having the wheels 10resting upon the track' 8. This construction permits the truck 9 to bemoved on the track in and out under the fire-box 7.

12 is a horizontal upper shaft and 13 a parallel lower shaft, both ofwhich are mounted in journal-boxes supported by the upwardly extendedsides of the truck 9.

14 are sprocket-drums mounted upon each of the shafts 12 and 13, and 15is a traveling or chain grate forming an endless apron which passesaround both of the drums 14. The shaft 12, beinghigher than the shaft13, causes the upper end of the traveling grate 15 to elevated. Theupper shaft 12 has a pulley 16 (shown in dotted lines -Fig. l), which isdriven from any suitable motor by the belt 17.

Located under the traveling grate 15 are a series of horizontalconveyor-troughs 18, the number depending upon the .width of thefire-box, which may vary with the size of the boilers. Each of theseconveyer-troughs Patented S ept. 3, 1907.

is provided with a longitudinal screw-conveyer 20, the front end of theshaft of which carries the bevel gear wheel 21.

22 is the oblique bottom of coal-chute located under, the travelinggrate 15 and into this chute the coal to be used as fuel will dumped,and will, be deposited by gravity upon the conveyors 20 in'the troughs18. Supported by the truck 9 and located at the rear of each of thetroughs18 are the inverted.

conical, vertical, coal chutes 24. These have inlet openings 25 at theirlower ends at diametrically opposite sides of the chutes. Each of thosevertical chutes 24 have their lower ends located'in the extensions 26,of the chutes 18. The bottoms of the extensions 26. are oblique, ,andslope downwardly from the chutes 18 so as to carry the fuel from theends of the latter, by'gravity, to the openings 25 in the verticalchutes 24. The upper ends of the chutes 24 terminate above the lowerinner ends of thetraveling grate 15, and have the forwardly obliquedeflecting plate 30 to direct the discharge'from the chute in thedirection of the grate-bar. The upper end of the chute 24 also has theoblique plate 31, down which the fuel discharged from said chute willtravel by gravity and will'be deposited upon the traveling grate 15.Located within the chute 24 is the vertical screw-conveyor 33, the wingsof which increase in width or-radius from the lower end of the chuteoutwardly to correspond with the increase in diameter of the conicalwalls of the chute. The object in mak-' ingthe walls of the chute 24 ofgradually increasing diameter from lower to upper'end'of the chute is toavoid the pa'ckingof the fuel within said chute; and

to prevent the fuel contents of the vertical chute from being carriedaround by the conveyor-screw without advancing upwardly, the walls ofthe chute will be provided with the longitudinal corrugations 34. Thewalls of these corrugations, on the side toward which the conveyer istraveling, will preferably be more abrupt than the other wall. of thesame corrugation so as to more positively resistthe motion of rotationimparted by-the screw-conveyer. I

Mounted on the truck 9 are the horizontal shafts 38.

These shafts will be geared together by' any suitable means, here shownas by means of a link belt 40, which connects the sprocket-wheels 41mounted on each of said shafts 38.

42 is a ratchet-wheel here shown forward end of one of the shafts 38. i43 is a yoke mounted on the'shaft 38, over the sprocket wheel 42, andhaving a lever extension by means of which the yoke is reciprocated.

44 is a pawl, carried by the yoke, which engages the teeth of theratchet-wheel 42 so as to move the ratchetas mounted on the wheelforward by the reciprocatory movement of the yoke and its lever. Theswinging movement of said lever and yoke will be imparted in anysuitable manner. i

Carried by the truck 9 and mounted at right angles to the shafts 38 arean equal number of vertical shafts 50. Mounted on the upper end of each.shaft 50 is a beveled pinion 51 meshing with the beveled wheel 2]. onthe shaft of the conveyor 20, and mounted on the lower end of each shaft50 is a bevel'wheel 53 which meshes with a like bevel wheel 54 on theadjacent shaft 38. The inner end of each shaft 38 carries a bevel wheel56 which meshes with a bevel wheel 57 on tholower end of the shaft ofthe adjacent conveyer.33.

liy the above construction, the rotation of shafts 38' will impart asimultaneousrotary .movement to both screw-conveyors 20 and 33.

My invention is capable of variation in many of its details ofconstruction Without departing from the spirit of this invention, and Itherefore do not desire to be limited to the exact device shown, but

chute at the rear of the grate having a top discharge upon said gratethe interior walls of said chute having longitudinal channels, aconveyer-screw rotating in said chute,

a second chute under the grate discharging into the lower end of thevertical chute and a conveyer-screw rotating in said second chute.

2. in a furnace, a grate, an upright-fuel chute at the rear of the gratehaving a top discharge upon said grate, the diameter of said chuteincreasing gradually from bot tom to top, the. interior walls of saidchute having longitudinal channels, a conv'e'yer-screw rotating "in saidchute and means, for supplying fuel to the lower end of said chute.

2;. in a furnace, a grate, an upright fuel-chute at the rear of thegrate having a top discharge upon said grate,

the. diameter of said chute increasing gradually from bottom to top,inside longitudinal channels in said chute having angular walls one ofwhich is in a plane approximately radial with relation to the center ofthe chute, a longitudinally,disp osed revoluble conveyor-screw in saidchute rotating toward the radially disposed walls of the longitudinalchute-channels, and means for delivering fuel to the bottom of saidchute.

4. In a furnace, a movable grate sloping upwardly from rear to the frontof the fire-box, an upright fuel chute discharging upon the rear of thegrate said chute having a gradual increase in diameter from the bottomto the top with annular longitudinal inside corrugations, a conveyerscrew rotating in said chute said screw standing longitudinally ofthechute and having blades increasing in width proportionately with theincreased diameter of the chute said chute having bottom inlets, asecond chute under the grate discharging into the lower end of theupright chute, a conveyer-screw rotating, in the second chute, and meansfor advancing the grate to gradually carry the fuel from back to thefront of the firebox.

5. In a furnace, a truck 'mounted on wheels a grate mounted on saidtruck, an upright fuel-chute at the rear of the grate having a topdischarge upon said grate and carried by said truck, a convey'er-screwrotating in said chute, a second chute under the grate carried by saidtruck and discharging into the lower end ,of the vertical-chute and aconveyor-screw in said second chute.

6. In a furnace, afire-box, rails forming a track on the floor below thefire-box and extending out forwardly of the furnace, a truck, flangedwheels on said truck whereby the latter is mounted on said track, amovable grate sloping upwardly from rear to front of the fire-box andmounted on said truck, an upright fuel chute at the rear of the gratehaving a top discharge upon said grate, said chute EUGENE BRETNEY. [13.5.]

' Witnesses;

F. W. Wommnn, L. B. WoimNna.

